TWI644497B - Electronic componets, wireless power communication device, wireless power transmission system and related control methods - Google Patents

Abstract

An electronic component used in a wireless power transmitter or a wireless power receiver includes a control circuit for adjusting a coupling coefficient K between the wireless power transmitter and the wireless power receiver and the wireless power reception The load quality factor Q of the machine so that the product of K and Q is less than a constant.

Description

Electronic components, wireless power communication equipment, wireless power transmission systems and related Control method

The invention relates to the technical field of wireless power transmission, and in particular to an electronic component, a wireless power communication device, a wireless power transmission system, and a related control method.

Wireless power transfer systems (WPTS) have become more and more popular as power is transmitted in a simple manner without using cables or connectors. WPTS currently used in the industry can be divided into two main types: Magnetic Induction (MI) systems and Magnetic Resonance (MR) systems. Both types of systems include wireless power transmitters and wireless power receivers. Both types of systems can be used to power or charge mobile devices (eg, smartphones, tablets, etc.) in other applications.

Inductive WPTS systems typically operate in a specified frequency range of several hundred hertz, which uses frequency changes as a power control mechanism. Magnetic resonant WPTS systems typically operate at a single resonant frequency, which uses input voltage regulation to regulate output power. In a typical application, a magnetic resonance WPTS system operates at a frequency of 6.78 MHz.

Many industry committees have worked to advance international standard.

The invention discloses an electronic component, a wireless power transmitter / receiver, a wireless power transmission system and a related control method, which can enable a transfer function between a wireless power transmitter and a wireless power receiver to drive a frequency of a wireless power transmitter. Keep monotonic in range.

An electronic component provided by the present invention is used in a wireless power transmitter or a wireless power receiver. The electronic component includes a control circuit for adjusting a coupling between the wireless power transmitter and the wireless power receiver. At least one of a coefficient K and a load quality factor Q of the wireless power receiver, so that a product of K and Q is less than a constant.

A wireless power communication device provided by the present invention is a wireless power transmitter or a wireless power receiver, and may include the electronic component according to the present invention.

A method for controlling a wireless power transmitter or a wireless power receiver provided by the present invention may include: adjusting a coupling coefficient K between the wireless power transmitter and the wireless power receiver and a load of the wireless power receiver At least one of the quality factors Q such that the product of K and Q is less than a constant.

It can be known from the above that in the present invention, at least one of the coupling coefficient K between the wireless power transmitter and the wireless power receiver and the load quality factor Q of the wireless power receiver is adjusted, so that the product of K and Q is less than A constant, thereby enabling the transfer function between the wireless power transmitter and the wireless power receiver to be monotonic within the frequency range of the driving signal of the wireless power transmitter.

100‧‧‧Wireless Power System

1‧‧‧ wireless power transmitter

2‧‧‧ regulated source

7‧‧‧Drive circuit

3‧‧‧ Inverter

6, 13‧‧‧ matching network

10‧‧‧Transmitter coil

9‧‧‧ signal generator

5‧‧‧controller

11‧‧‧Wireless Power Receiver

12‧‧‧ receiver coil

14‧‧‧ Rectifier

15‧‧‧DC-DC converter

16‧‧‧Control unit

Vout‧‧‧Output voltage

20, 22, 24, 30, 32, 34 ‧‧‧ curves

Ro‧‧‧ apparent resistance

40, 60, 70, 80, 90, 1000 ‧ ‧ ‧ methods

42, 44, 62, 63, 64, 72, 73, 74, 82, 83, 84, 92, 93, 94, 102, 103, 104

52‧‧‧Current measuring device

54‧‧‧ Resistive Impedance

56‧‧‧Voltage measuring device

58‧‧‧Load

FIG. 1 shows a block diagram of the wireless power system 100.

Figure 2 shows the size response coordinates of the three transfer functions in the case where the transmitter coil and the receiver coil are at three different distances.

Figure 3 shows the effect on the transfer function in Figure 2 when the distance between the transmitter coil and the receiver coil remains the same, but the load condition is reduced by increasing Ro from 3.3 ohms to 9.9 ohms.

FIG. 4 is a flowchart of a method 40 for maintaining a monotonic behavior of a transfer function.

FIG. 5 illustrates an embodiment of a wireless power receiver 11 for a wireless power transmission system.

FIG. 6 is a flowchart of a method of controlling the resistance of a receiver to maintain a monotonic behavior of a transfer function.

FIG. 7 is a flowchart of a method for controlling the inductance or capacitance of a receiver to maintain the monotonic behavior of a transfer function.

FIG. 8 is a flowchart of a method for controlling a coupling coefficient of a receiver to maintain a monotonic behavior of a transfer function.

FIG. 9 is a flowchart of a method for controlling a target voltage of a receiver to maintain a monotonic behavior of a transfer function.

FIG. 10 is a flowchart of a method of controlling the operating frequency of a receiver to maintain a monotonic behavior of a transfer function.

In order to explain the technical content, structural features, achieved objectives and effects of the present invention in detail, the present invention is described in detail below with reference to the drawings and embodiments.

Certain terms are used in the description and the scope of subsequent patent applications to refer to specific elements. Those skilled in the art should understand that hardware manufacturers may use different names to refer to the same component. This document does not use the differences in names as a way to distinguish components, but rather uses the functional differences of components as a criterion for distinguishing components. In the following description and the scope of the patent application, the terms "including" and "including" are open-ended terms and should be interpreted as "including but not limited to". In addition, "coupled" The term includes direct and indirect means of electrical connection. Therefore, if one device is coupled to another device, it means that the one device can be directly electrically connected to the other device, or indirectly electrically connected to the other device through other devices or connection means.

In WPTS, a wireless power transmitter and a wireless power receiver may be inductively coupled to each other. Due to factors such as the distance between the wireless power transmitter and the wireless power receiver, the coil geometry, or the coil position, the wireless power transmitter and the wireless power receiver can be loosely coupled to each other, that is, the coupling coefficient between them may be relatively low. When at least one of the distance and position of the wireless power receiver and the load seen by the wireless power receiver changes, the load impedance seen by the wireless power transmitter is at least partially within a wide range due to the change in coupling. Variety. For example, when multiple receivers are placed close to the transmitter, or when the loss level of a battery charged by the transmitter changes, or when the charging rate of the battery changes, what the wireless transmitter sees The load impedance may vary.

WPTS's transfer function describes the power transmitted in a frequency range. The magnitude of the transfer function will peak at the resonance frequency of the system. Sometimes it is desirable to operate the system at a higher frequency than the resonant frequency. In practical systems, this method of operation has benefits for soft handover in semiconductor devices, which reduces power loss during soft handover in WPTS. In some embodiments, assuming that the transfer function is monotonic at a frequency greater than the resonance frequency, the frequency of the drive signal (the frequency used to drive the inverter 3) becomes higher from the system resonance frequency F0. In the near future, the greater the amount of power transferred. The further away from the resonance frequency F0, the less power is transmitted. In actual WPTS, the driving frequency varies between a high operating frequency F2 and a low operating frequency F1. This will allow WPTS to well control the quality of the transmitted power by adjusting the frequency used to transmit the power. However, the inventors have found that in some load and / or coupling combinations, the transfer function can become non-monotonic above the resonant frequency, exhibiting a resonance peak split; the resonant frequency will become practical Above F0. Because when the frequency exceeds the maximum value of the transfer function, the frequency control method may The transmitted power cannot be effectively controlled, so it is not desirable to operate at a frequency greater than the maximum value of the transfer function. When the transfer function is non-monotonic above the resonance frequency, the frequency range of the drive signal of the WPTS will be reduced to be between the maximum value of the transfer function and the high operating frequency F2. In addition, because the non-monotonic behavior is lower than the local maximum of the transfer function, the level of power that can be transmitted may also shrink. Either of these two effects will prevent the system from reaching the desired power level in a particular drive signal frequency range. The technology described herein allows a wireless power transmission system to operate in a specified frequency range and obtain a desired level of power transmission. The inventors have appreciated system parameters that ensure that the transfer function monotonically spans the frequency range of the drive signal, and have developed techniques for adjusting one or more parameters of the system to maintain the monotonic behavior of the transfer function. According to some embodiments, such techniques require adjusting one or more system parameters to maintain the relationship between the coupling coefficient between the transmitter coil and the receiver coil and the load quality factor of the receiver coil.

FIG. 1 shows a block diagram of a wireless power system 100 including a wireless power transmitter 1 and a wireless power receiver 11. The wireless power transmitter 1 includes a driving circuit 7 including an inverter 3 for driving the transmitter coil 10 through a matching network 6. The wireless power transmitter 1 may include a voltage regulator source 2 (for example, a voltage regulator) for supplying a stable DC voltage to the inverter 3. The voltage stabilization source 2 generates a stable DC output voltage according to the control stimulus output by the controller 5. In some embodiments, the driving circuit 7 may be a soft-switched power converter, for example, for converting a DC voltage to an AC output voltage at the input of the inverter 3 to drive the transmitter coil 10 Class E amplifier. Providing an AC output voltage makes wireless power transmission possible through electromagnetic induction. The controller 5 may control the signal generator 9 to drive the inverter 3 using a signal having a selected wireless power transmission frequency. As an example, the inverter 3 may perform switching in a frequency range of 100kHz-205kHz to transmit power to a wireless power receiver that expects to receive wireless power according to a figure of merit of a corresponding low power quality factor receiver, and the inverter 3 is in The frequency range of 80kHz-300kHz is switched to transmit power to a medium power figure of merit receiver. Inverter 3 switches at a higher frequency, for example, in the ISM wave Band and a frequency greater than 1 MHz, for example, 6.765 MHz-6.795 MHz, to transmit power to a receiver that expects to receive wireless power using magnetic resonance technology. However, these frequencies are for example only, as wireless power can be transmitted on a variety of suitable frequencies in accordance with any suitable specification. The controller 5 may be an analog circuit, a digital circuit, or a combination thereof. The controller 5 may be programmable, and may control the signal generator 9 to generate a signal at a desired transmission frequency according to a stored program instruction, so that the inverter 3 switches at the desired transmission frequency. The matching network 6 can promote the transmission of wireless power by exhibiting an appropriate impedance to the inverter 3. The matching network may include one or more capacitive or inductive elements, or any combination of any capacitive or inductive elements. Since the transmitter coil 10 may include an inductive impedance, in some embodiments, the matching network 6 may include one or more capacitive elements. When these capacitive elements are combined with the transmitter coil 10, the output of the inverter 3 may be The terminal exhibits an impedance suitable for driving the transmitter coil 10. In some embodiments, during the wireless power transmission, the resonance frequency of the matching network 6 may be equal to or approximately equal to the switching frequency of the inverter 3. The transmitter coil 10 may be implemented by any suitable type of conductor. The conductor may be a conductive wire (including solid wires or stranded wires), or a patterned conductor (for example, a patterned conductor of a printed circuit board or integrated circuit).

The alternating current at the transmitter coil 10 generates an oscillating magnetic field according to the Ampere's Law. The oscillating magnetic field induces an AC voltage to the receiver coil 12 of the wireless power receiver 11 according to Faraday's law. The AC voltage induced at the receiver coil 12 is provided by the matching network 13 to the rectifier 14 to generate an unstable DC voltage. The rectifier 14 may be a synchronous rectifier or may be implemented using a diode. The unstable DC voltage is adjusted by the DC-DC converter 15, and the output of the DC-DC converter 15 is further filtered and provided to the load as the output voltage Vout. In some embodiments, the DC-DC converter 15 may be a linear regulator, a buck regulator, a boost regulator, a flyback regulator, or any other suitable converter. The control unit 16 may be an analog circuit, a digital circuit, or a combination thereof, and the control unit may be programmed. In some embodiments, the control circuit 16 may be included in the rectifier 14 or the DC-DC converter 15 or separated into multiple components. The control unit 16 may be located in the rectifier 14 and the DC-DC converter in some embodiments. 器 15。 Between converters 15.

As mentioned earlier, the operation of the wireless power system 100 may be limited by the characteristics of the system's transfer function. Figure 2 shows the size response coordinates of the three transfer functions in the case where the transmitter coil and the receiver coil are at three different distances. In coordinates, the x-axis represents the frequency (unit: kilohertz), and the y-axis represents the size of the transfer function. The transfer function curves are shown in the figure. The coils 10 and 12 use the same type of coil, and the load at the wireless power receiver is 3.3 ohms. Curve 20 shows the transfer function at a coil distance of 6 mm. Curve 22 shows the transfer function at a coil distance of 3 mm. Curve 24 shows the transfer function at a coil distance of 0 mm.

As shown in the figure, in the frequency range of the driving signal, curve 20 is monotonic, and curves 22 and 24 are non-monotonic. As shown in Fig. 2, when the transmitter coil and the receiver coil are close to each other, the coupling between the transmitter coil and the receiver coil is increased, and thus the transfer function of the system may become non-monotonic. For a desired driving signal frequency range of 110 kHz-180 kHz, since curve 20 exhibits a monotonic behavior over the entire frequency range, curve 20 is a suitable transfer function. However, in the range of 110kHz-180kHz, curves 22 and 24 are non-monotonic, and they have resonance frequencies at approximately 120kHz and 145kHz, respectively. Therefore, for curves 22 and 24, adjusting the system's driver frequency using typical frequency control techniques may not produce the desired adjustment in resonance-based power transmission. When the operation is limited to the right side of the resonance in both cases, the range of output power will be limited. Since the output power range and the drive signal frequency range become narrower as the coupling between the coils increases, limiting the power range will limit the maximum power that can be transmitted and control the power that can be transmitted. The size ranges of the curves 22 and 24 are both smaller than the size range of the curve 20, which results in restrictions on the control of power transmission and reduces the maximum value of power transmission. It should be noted that although this embodiment shows that the distance between the coils causes the transfer function to generate non-monotonic behavior within the frequency range of the drive signal, as described later, there are other factors that can also form the non-monotonic behavior of the transfer function.

Fig. 3 shows that the distance between the transmitter coil and the receiver coil remains the same, but when the load condition is reduced by increasing Ro from 3.3 ohms to 9.9 ohms, the effect on the transfer function in Fig. 2 ring. As shown in FIG. 3, reducing the load condition by increasing Ro makes all transfer functions monotonic. Adjusting Ro is equivalent to adjusting the quality factor Q by adjusting the load of the wireless power receiver. Figure 3 shows multiple transfer functions, all of which exhibit monotonic behavior. As in Figure 2, in the coordinates, the x-axis represents the frequency (unit: kilohertz), and the y-axis represents the size of the transfer function. In representing these transfer function curves, the coils 10 and 12 use a standard coil type, and the load at the wireless power receiver is 9.9 ohms. Curve 30 shows the transfer function at a coil distance of 6 mm, and curve 30 is the monotonic transfer function of the system. Curve 32 shows the transfer function at a coil distance of 3 mm. Curve 34 shows the transfer function at a coil distance of 0 mm. The three curves exhibit a monotonic behavior over the entire drive signal frequency range of 110kHz-180kHz. The driving signal frequency range listed here should not be considered as a limitation of the present invention, but only used to describe the example of the monotonic behavior of the transfer function of the WPTS. As described below, increasing Ro decreases the load quality factor Q. Reducing the load quality factor Q can make the transfer function from non-monotonic to monotonic in the frequency range of the driving signal.

The inventors have recognized that specific system conditions are selected or controlled to make the transfer function monotonic over the drive signal frequency range. In particular, the inventors have recognized that as long as the product between the coupling coefficient K of the primary and secondary coils and the quality factor Q of the loaded secondary coil does not exceed a constant, the transfer function will be monotonic in the frequency range of the drive signal. In the equation: K * Q <C, C is a constant. In some embodiments, C may be 1, or a value between 0.8, or 0.8-1, or another suitable value. As long as the equation is satisfied, the transfer function of WPTS will be monotonic at resonance. Design or control a wireless power transmission system such that the above equations are satisfied, allowing the transfer function to be monotonic for any desired load, coupling, and coil distance. This situation can be satisfied by designing K or Q, or K and Q can be controlled to maintain the above relationship. One or more of K or Q can be adjusted to maintain the above relationship.

Control of K and / or Q can be achieved in a number of ways. K is determined by physical size and relationship, and Q is preferably determined by electronic relationship. Q can be expressed as:

Among them, Ls is the inductance of the receiver 11, Cs is the capacitance of the receiver 11, Ro is the apparent resistance of the receiver 11, and r is the parasitic resistance of the receiver 11. Any of these variables can be used to control Q to establish or maintain the monotonic behavior of the WPTS transfer function.

Next, a method of maintaining the relationship described above by controlling K or Q will be discussed. FIG. 4 is a flowchart of a method 40 for maintaining a monotonic behavior of a transfer function. The method 40 may include an act 42 including measuring a characteristic of the receiver 11. As shown in FIG. 5, the characteristic may be at least one of current, voltage, or other suitable characteristics of the signal at the receiver 11. Act 44 may include adjusting at least one of the quality factors defining the quality factor Q and the coupling coefficient K so that the product of Q and K is lower than the constant C. This method can occur many times in the process of wireless power transmission to ensure that the transfer function remains monotonous during the wireless power transmission, or the method occurs only once during the wireless power transmission. In some embodiments, the method shown in FIG. 4 may be executed by the control unit 16 and / or the controller 5 (that is, the control unit 16 or the controller 5 in the embodiment of the present invention may be used to adjust the coupling coefficient K Or the control circuit of electronic components with quality factor Q).

Next, the use of the above technique in a wireless power receiver circuit will be described. FIG. 5 illustrates an embodiment of a wireless power receiver 11 for a wireless power transmission system. As mentioned previously, the wireless power receiver 11 may include a receiver coil 12, a matching network 13, a rectifier 14, a DC-DC converter 15, and a control unit capable of communicating with a wireless power transmitter in-band or out-of-band. 16. The receiver 11 may further include a current measurement device 52, a voltage measurement device 56, a resistive impedance 54, and a load 58. In some embodiments, the current measurement device 52 and / or the voltage measurement device 56 may be part of the control unit 16. In some embodiments, the resistive impedance 54 may be a manifestation of the equivalent impedance of the DC-DC converter 15 and the load 58, rather than a real circuit element, and therefore represents Ro in the aforementioned equation. In some implementations In the example, only one current measurement device 52 and one voltage measurement device 56 are required, or any other measurement device suitable for measuring the characteristics of the signal of the receiver 11 may be used. In some embodiments, the control unit 16 uses the measurement results of the measurement devices 52 and / or 56 to change the operating conditions of the DC-DC converter 15 in a manner that dynamically adjusts the equivalent load 54 of the rectifier 14 using the previously described techniques operating condition) to maintain the monotonicity of the transfer function of the wireless power system. For example, when the DC-DC converter 15 is a step-down converter, the equivalent impedance 54 as the measurement result of the measurement devices 52 and 56 is estimated to be too low to meet the standard Q * Ro> constant, either within the bandwidth or the bandwidth The external communication control unit 16 may request to increase the rectifier output voltage and may also control to reduce the duty cycle factor of the converter 15, so that the output of the receiver will not change.

In one embodiment, Q can be controlled by adjusting Ro using the method 60 shown in FIG. 6. This embodiment can be used alone or combined with other control mechanisms described in the present invention. In this embodiment, the resistor 54 may be an adjustable impedance unit, for example, a variable resistor or a stack of switched resistors, or the equivalent resistance of other parts of the receiver 11 as described above. In act 62, characteristics of the receiver, such as the voltage or current of the signal may be measured. In act 63, it is verified whether the product of K and Q is less than the constant C. In act 64, the control unit 16 may control the value of the resistor 54 so that the product of the quality factor and the coupling coefficient is lower than the constant C. When the resistor 54 is an adjustable impedance unit, the value of the resistor 54 can be directly controlled, or the equivalent resistance 54 can be changed by controlling the current or voltage flowing from the rectifier 14 (the following figure illustrates how to use an example The voltage output from the rectifier 14 is controlled to change the equivalent resistance 54). Due to the DC-DC converter 15, the output voltage is always kept approximately constant, which can reduce changes in voltage and / or current caused by adjusting the value of the resistor or adjusting the value of Ro.

In one embodiment, the method 70 shown in FIG. 7 can be used to adjust C and / or L to control Q. The method of this embodiment can be used in combination with any other control mechanism described. C and / or L can be controlled in various ways. C can be adjusted by controlling a frequency-dependent capacitor, a voltage-dependent capacitor, a switched capacitor stack, or any other component whose capacitance can be adjusted. Similarly, any L can be adjusted by a variable capacitance element, a switching inductance element, or an adjustable tap of the receiver coil 12. In act 72, a characteristic of the receiver is measured, such as the voltage or current of the signal. In act 73, it is verified whether the product of K and Q is less than the constant C. In act 74, the control unit 16 may control the value of L or C so that the product of the figure of merit and the coupling coefficient is less than the constant C.

In one embodiment, K may be controlled using the method 80 shown in FIG. The method of this embodiment can be used in combination with any other control mechanism described. In act 82, a characteristic of the receiver is measured, such as a voltage or current of the signal. In act 83, it is verified whether the product of K and Q is less than the constant C. In act 84, the control unit 16 may control the value of K so that the product of K and Q is less than the constant C. Various methods can be used to control K, for example, by a mechanical system regarding the coupling distance between transmitter coil 10 and receiver coil 12. The mechanical system can use the standoff distance under the control of the control unit 16 to generate a specific minimum distance to keep K less than the maximum value.

In one embodiment, the method 90 shown in FIG. 9 may be used to control the wireless power receiver target voltage. The method of this embodiment can be used in combination with any other control mechanism described. At act 92, a characteristic of the receiver is measured, such as the voltage or current of the signal. In act 93, it is verified whether the product of K and Q is less than the constant C. In act 94, the control unit 16 may control the target voltage of the wireless power receiver to change the equivalent impedance 54 so that the product of K and Q is smaller than the constant C. For example, if the wireless power transmission system operates in a closed loop control environment, the rectifier output voltage may be a voltage controlled by the closed loop loop. When the control loop controls the output voltage of the rectifier so that the output voltage is equal to the target voltage, the rectifier output voltage may be nominally referred to as the "target voltage".

In one embodiment, the method 1000 shown in FIG. 10 may be used to control the operating frequency of the wireless power transmitter (ie, the frequency of the signal transmitted by the transmitter coil). The method of this embodiment can be used in combination with any other control mechanism described. In act 102, a characteristic of the receiver is measured, such as a voltage or current of a signal. In act 103, it is verified whether the product of K and Q is less than the constant C. In act 140, the controller 5 can control the use of the in-band communication or out-of-band communication link as the control unit 16. The operating frequency of the wireless power transmitter further adjusts the quality factor Q so that the product of K and Q is less than the constant C.

As mentioned earlier, the controller 5 can be used to control the wireless power transmitter and the control unit 16 can be used to control the wireless power receiver. The controller 5 and the control unit 16 can be implemented using any suitable type of circuit. For example, the controller 5 and the control unit 16 may be implemented by hardware or a combination of hardware and software. When implemented in software, suitable software code can be executed on any suitable processor or collection of processors. The one or more controllers may be implemented in various ways, for example, using dedicated hardware or general-purpose hardware (e.g., one or more processors) designed by microcode or software programming to perform the functions described above.

The parts of the device and technology described in the present invention can be used independently, or in combination, or in other ways not previously described in the present invention. Therefore, the present invention is not limited to the previously described or illustrated in the drawings. Application or arrangement of components. For example, components described in one embodiment may be combined with components described in other embodiments in any way.

The use of ordinal numbers such as "first" and "second" in the scope of the patent application does not imply any priority, order of priority, order between elements, or chronological order of executed methods, and Used only as an identifier to distinguish between different elements with the same name (with different ordinal numbers). The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the scope of the present invention.

Claims (22)

An electronic component used in a wireless power transmitter or a wireless power receiver includes a control circuit for adjusting a coupling coefficient between the wireless power transmitter and the wireless power receiver and the wireless power receiver At least one of a load quality factor of the wireless power receiver, so that the product of the coupling coefficient and the load quality factor is less than a constant and satisfies the transfer function of the wireless power transmission system. According to the electronic component described in the first item of the patent application scope, the control circuit is further configured to measure an electronic characteristic of the wireless power receiver, and adjust the load quality factor according to the electronic characteristic. According to the electronic component according to item 2 of the patent application scope, the control circuit includes at least one of a current measuring device and a voltage measuring device. According to the electronic component described in item 1 of the patent application scope, the control circuit is configured to adjust at least one of a capacitor, an inductor, a resistor, and a load of the wireless power receiver to adjust the load quality factor. According to the electronic component described in claim 4 of the patent application scope, the control circuit adjusts the capacitance by controlling a variable capacitance of the wireless power receiver. According to the electronic component described in claim 4 of the patent application scope, the control circuit adjusts the inductance by controlling a variable inductance of the wireless power receiver. According to the electronic component described in claim 5, the control circuit adjusts the resistance by controlling a variable equivalent resistance of the wireless power receiver. According to the electronic component described in item 1 of the patent application scope, the control circuit is used to adjust an operating frequency of the transmitter to adjust the load quality factor. The electronic component as described in claim 1, wherein the control circuit sets or changes a minimum between a transmitter coil of the wireless power transmitter and a receiver coil of the wireless power receiver. Distance to adjust the coupling coefficient. According to the electronic component described in any one of claims 1-9, the constant is 0.8 or more and 1 or less. A wireless power communication device is a wireless power transmitter or a wireless power receiver, and includes electronic components as described in patent application scope 1. A method for controlling a wireless power transmitter or a wireless power receiver, comprising: adjusting a coupling coefficient between the wireless power transmitter and the wireless power receiver and a load quality factor of the wireless power receiver At least one of them, so that the product of the coupling coefficient and the load figure of merit is less than a constant and satisfies the transfer function monotony of the wireless power transmission system. According to the method of claim 12 in the patent application scope, at least one of the coupling coefficient between the wireless power transmitter and the wireless power receiver and the load quality factor of the wireless power receiver is adjusted. One step includes: measuring an electronic characteristic of the wireless power receiver, and adjusting the load quality factor according to the electronic characteristic. According to the method of claim 13 in the patent application scope, the electronic characteristic includes at least one of a current and a voltage. According to the method of claim 12 in the patent application scope, at least one of the coupling coefficient between the wireless power transmitter and the wireless power receiver and the load quality factor of the wireless power receiver is adjusted. One step includes adjusting the load quality factor by adjusting at least one of a capacitance, an inductance, a resistance, and a load of the wireless power receiver. According to the method described in claim 15, the capacitance is adjusted by controlling a variable capacitance of the wireless power receiver. According to the method described in claim 15, the inductance is adjusted by controlling a variable inductance of the wireless power receiver. According to the method described in claim 15, the resistance is adjusted by controlling a variable resistance of the wireless power receiver. According to the method of claim 12, the coupling is adjusted by setting or changing a minimum distance between a transmitter coil of the wireless power transmitter and a receiver coil of the wireless power receiver. coefficient. According to the method of any one of claims 12-19, the constant is greater than or equal to 0.8 and less than or equal to 1. A wireless power transmission system includes: a wireless power transmitter; a wireless power receiver; wherein at least one of the wireless power transmitter and the wireless power receiver is used to maintain the wireless power transmitter and the wireless power transmitter; At least one of a coupling coefficient between wireless power receivers and a load quality factor of the wireless power receiver, so that the product of the coupling coefficient and the load quality factor is less than a constant and meets the transfer of the wireless power transmission system The function is monotonic. According to the wireless power transmitting system described in item 21 of the scope of patent application, the constant is greater than or equal to 0.8 and less than or equal to 1.